Separate user and global packages, default to user

Requires Cabal >= 1.18.

Specify --global to process global packages.
Specify --all to process user and global packages.

Bump version to v0.6.0.0.

Delete shared directory as well as Haddock directory

Update README for delete policy change and info output

Bump version.

Initial recursive support by -R option.

Bump version to v0.2.4.0.
Use <$> instead of fmap.
Drop deepseq dependency.